The Mini Powercore 4 is the best bang for your buck performance bolt-on for your mini. Offered as a closed course moto muffler or as a spark arrestor version, the Mini Powercore 4 features a Hi-Flo stainless steel core and formed endcaps, an aircraft-grade aluminum canister and a durable stainless steel header. Its pounds lighter than stock and you will swear the motor has been bored and stroked with the first twist of the throttle. Hi-Flo core and end cap. Pounds lighter than stock. Detailed Specifications: Type: System. Header construction: Stainless steel. Header type: Hi-Flo. Weight: 3.0 pounds. Note: For closed course competition use only. Not intended for street use.